SplitPushButton setSizePolicy is not working properly

[immiProgrammer]

VID_20230724_210802.mp4

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *
import sys
from qfluentwidgets import *

class Demo(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        QHBoxLayout(self)
        AddCustomerSplit = SplitPushButton('Add Customer', self, FluentIcon.ADD)
        self.layout().addWidget(AddCustomerSplit)
        AddCustomerSplit.setSizePolicy(PushButton().sizePolicy())

if __name__ == '__main__':
    # enable dpi scale
    QApplication.setHighDpiScaleFactorRoundingPolicy(Qt.HighDpiScaleFactorRoundingPolicy.PassThrough)
    QApplication.setAttribute(Qt.AA_EnableHighDpiScaling)
    QApplication.setAttribute(Qt.AA_UseHighDpiPixmaps)

    app = QApplication(sys.argv)
    w = Demo()
    w.show()
    sys.exit(app.exec())